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BEGIN:VEVENT
DTSTART;TZID=Europe/London:20260327T140500
DTEND;TZID=Europe/London:20260327T145500
DTSTAMP:20260412T204135
CREATED:20260119T130832Z
LAST-MODIFIED:20260324T103227Z
UID:477-1774620300-1774623300@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 2\, Week 8: Prof John King\, University of Nottingham
DESCRIPTION:Academic Webpage \nTitle: Wave propagation in reaction-diffusion equations \nAbstract: I’ll talk about a broad class of scalar nonlinear parabolic equations\, extending the established concepts of pulled and pushed fronts (conventional travelling waves of constant speed) to more extreme cases that allow the classification of the variety of potential behaviour. The work is motivated by tissue-growth applications\, though I won’t have much to say about these; much of the classification follows from relatively routine calculations. \nLocation: Maths Lecture Theatre B
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/semester-2-week-8-prof-john-king-university-of-nottingham/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20260320T140500
DTEND;TZID=Europe/London:20260320T145500
DTSTAMP:20260412T204135
CREATED:20260121T140820Z
LAST-MODIFIED:20260316T162544Z
UID:482-1774015500-1774018500@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 2\, Week 7: Dr Ioana Colfescu\, University of St Andrews
DESCRIPTION:Academic Webpage \nTitle: From Linear Regression to Gaussian Neural Networks: Diagnosing the Evolving SST–NAO Teleconnection Under Climate Change Using Explainable Machine Learning \nAbstract: \nThe North Atlantic Oscillation — a large-scale seesaw in atmospheric pressure between the Azores and Iceland — is the single most important driver of winter weather variability across Europe and the North Atlantic. When it is strongly positive\, mild and wet westerly winds dominate Western Europe; when it is strongly negative\, cold Arctic air spills southward\, bringing severe winters to the British Isles and Scandinavia. Despite decades of research\, predicting the NAO weeks to months in advance remains one of the hardest problems in climate science.\n\nOne promising avenue is to use sea surface temperatures as predictors. The ocean warms and cools slowly compared to the atmosphere\, meaning that its current state carries memory of past conditions — and potentially information about future atmospheric behaviour. But reading that signal is difficult: it is weak\, geographically complex\, and — crucially — may not be stationary in time. As the climate warms\, the ocean is changing in ways that could alter\, strengthen\, or entirely reshape the statistical relationship between sea surface temperatures and the NAO.\n\nIn this study we ask two questions. First\, how well can machine learning models of increasing sophistication — from simple linear regression all the way to deep convolutional neural networks — predict the winter NAO from observed sea surface temperature patterns? Second\, and more importantly\, has that predictability changed between the early observational record (1950–1969) and the most recent decades (2004–2023)\, a period marked by accelerated warming\, dramatic Arctic sea ice loss\, and intensifying ocean circulation changes?\n\nWe find that predictive skill increases consistently as models become more complex\, with our most sophisticated model — a Gaussian Mixture neural network ensemble — also providing honest estimates of its own uncertainty. More strikingly\, predictive skill is systematically higher in the late period than in the early period across all model types. This points to a genuine strengthening of the ocean–atmosphere connection driving the NAO\, likely as a consequence of climate change making oceanic temperature patterns more extreme and more spatially organised.\n\nLocation: Maths Lecture Theatre B
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/semester-2-week-7-dr-ioana-colfescu-university-of-st-andrews/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20260313T140500
DTEND;TZID=Europe/London:20260313T145500
DTSTAMP:20260412T204135
CREATED:20260119T130147Z
LAST-MODIFIED:20260309T111248Z
UID:473-1773410700-1773413700@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 2\, Week 6: Prof John Mackenzie\, University of Strathclyde
DESCRIPTION:Academic Webpage \nTitle: Dissecting the Role of Phenotypic Variation in Cell Population Growth and Collective Self-Generated Chemotaxis \nAbstract: \nPhenotypic variation is a ubiquitous feature of biological cell populations\, even in genetically identical cells growing in uniform environments. Such variability can have profound consequences for population-level behaviour\, particularly under stress\, yet it is often neglected in classical modelling frameworks. \nIn the first part of this talk\, I consider mathematical models of bacterial population growth that explicitly incorporate non-heritable variation in individual cell growth rates. I examine how phenotypic heterogeneity and environmental selection shape population growth and the dynamics of phenotypic subpopulations. We derive theoretical results for population growth rates and compare them with predictions from homogeneous models\, identifying regimes in which variability qualitatively alters population outcomes. I also address the inverse problem of inferring distributions of generation times and phenotypic abundances from data\, showing that competing model assumptions can be robustly distinguished. \nIn the second part of the talk\, I turn to self-generated chemotaxis\, a collective process in which cells modify their chemical environment to guide movement. Using a hybrid discrete–continuum model that couples stochastic cell motion with a continuum description of the chemoattractant\, I investigate how phenotypic variation in motility\, sensing\, and chemical degradation affects the robustness of collective migration. Simulations and inference results highlight which sources of variability are most influential. The results and tools developed have broader implications for collective behaviour in cell biology\, ecology\, and evolution. \nLocation/Time: Maths Lecture Theatre B
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/semester-2-week-6-prof-john-mackenzie-university-of-strathclyde/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20260306T140500
DTEND;TZID=Europe/London:20260306T145500
DTSTAMP:20260412T204135
CREATED:20250710T155011Z
LAST-MODIFIED:20250710T155235Z
UID:456-1772805900-1772808900@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 2 Spring Vacation: No Seminar
DESCRIPTION:
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/semester-2-spring-vacation-no-seminar/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20260227T140500
DTEND;TZID=Europe/London:20260227T145500
DTSTAMP:20260412T204135
CREATED:20250710T154825Z
LAST-MODIFIED:20260223T093740Z
UID:454-1772201100-1772204100@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 2\, Week 5: Prof Eugene Benilov\, University of Limerick
DESCRIPTION:Academic webpage \nTitle: Phase transitions from the viewpoint of an applied mathematician \nAbstract: \nEvaporation\, supercooling\, and related phenomena can be described using hydrodynamic\, kinetic\, or mixed models – which yield results differing by up to two orders of magnitude.  Furthermore\, these theoretical predictions disagree with at least some experimental results\, which themselves are not mutually consistent: reported evaporation rates of the same liquid at the same temperature differ just as much as their theoretical counterparts. \nIn this talk\, I explain the origin of the discrepancies in the experimental data and argue that the only reliable theoretical description is provided by the Enskog–Vlasov kinetic equation. \nLocation: Maths Lecture Theatre B
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/semester-2-week-5-prof-eugene-benilov-university-of-limerick/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20260220T140500
DTEND;TZID=Europe/London:20260220T145500
DTSTAMP:20260412T204135
CREATED:20250710T154515Z
LAST-MODIFIED:20260212T105047Z
UID:451-1771596300-1771599300@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 2\, Week 4: Prof Caroline Terquem\, University of Oxford
DESCRIPTION:Academic webpage \nTitle: Turbulent damping of fast oscillations by a convective flow \nAbstract:Traditional mixing-length models describe tidal dissipation in convective flows as a large-scale oscillation damped by an effective turbulent viscosity that is artificially reduced when the oscillation period is much shorter than the convective turnover time.  This yields dissipation rates far below observational constraints. From first principles\, we have shown that this picture should be reversed for high-frequency oscillations: the fluctuations correspond to the tidal oscillation and the mean shear arises from large convective eddies. This framework yields an energy exchange rate coupling the oscillation’s Reynolds stress with the convective shear but it does not\, on its own\, specify whether energy flows into or out of the oscillation. Three-dimensional Rayleigh-Benard simulations with a radiative free surface show that the oscillations in fact transfer energy to the mean convective flow\, at the rate\sim u’^{2}/t_{conv}\, demonstrating strong correlations between fluctuation velocities and the large-scale shear. Within the simple equilibrium-tide framework\, this damping mechanism reconciles theory with observed dissipation. \nLocation: Maths Lecture Theatre B
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/semester-2-week-4-prof-caroline-terquem-university-of-oxford/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20260213T140500
DTEND;TZID=Europe/London:20260213T145500
DTSTAMP:20260412T204135
CREATED:20250710T154130Z
LAST-MODIFIED:20260212T104814Z
UID:448-1770991500-1770994500@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 2\, Week 3: Prof Oliver Jensen\, University of Manchester
DESCRIPTION:Academic webpage \nTitle: Multicellular Calculus \nAbstract: The disordered and granular nature of multicellular tissues endows them with exotic mechanical properties and presents challenges to continuum modelling frameworks.  To address this\, many researchers use the vertex model as a convenient computational tool with which to simulate epithelia\, the cell layers that coat developing embryos or provide protective barriers within the body.  Based on very simple constitutive assumptions\, the vertex model connects the shape of individual cells to their mechanical environment.  To facilitate analysis of the model\, we have developed tools of discrete calculus using a blend of mimetic finite differences and exterior calculus.  Using this machinery\, I will explain how puncturing a cell monolayer excites a discrete harmonic vector field that captures some features of a simulated laser-ablation experiment.  This approach illustrates how some familiar continuum modelling techniques may be adapted to describe disordered microstructured materials\, without relying on smoothness or regularity conditions \nLocation: Maths Lecture Theatre B
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/semester-2-week-3-prof-oliver-jensen-university-of-manchester/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20251128T140500
DTEND;TZID=Europe/London:20251128T145500
DTSTAMP:20260412T204135
CREATED:20250710T153721Z
LAST-MODIFIED:20260119T125901Z
UID:446-1764338700-1764341700@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 1\, Week 11: Prof Steve Tobias\, University of Edinburgh
DESCRIPTION:Academic webpage \nTitle: What can flow down a pipe teach us about the geodynamo (and other nonlinear stability problems)? \nAbstract: The Geomagnetic field is generated in the rapidly rotating fluid outer core of the Earth on a vast range of temporal scales. This leads to the presence of slow balanced motions and fast waves\, which is a complete pain for numerical approaches. In this talk I will examine a strategy for mapping out the landscape of dynamos in which the magnetic field has broken the constraints imposed by rotation and argue that this is the best approach to finding the “strong-field” branch of dynamo action at extreme parameters. The techniques used are very transferable and I will finish by discussing other problems where they might be useful.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/semester-1-week-11-prof-steve-tobias-university-of-edinburgh/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20251121T140500
DTEND;TZID=Europe/London:20251121T145500
DTSTAMP:20260412T204135
CREATED:20250710T153348Z
LAST-MODIFIED:20260119T125745Z
UID:442-1763733900-1763736900@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 1\, Week 10: Dr Oliver Allanson\, University of Birmingham
DESCRIPTION:Academic webpage \nTitle: Postponed to a later date.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/semester-1-week-10-dr-oliver-allanson-university-of-birmingham/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20251114T140500
DTEND;TZID=Europe/London:20251114T145500
DTSTAMP:20260412T204135
CREATED:20250710T152817Z
LAST-MODIFIED:20260119T125710Z
UID:440-1763129100-1763132100@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 1\, Week 9: Dr Lois Baker\, University of Edinburgh
DESCRIPTION:Academic webpage \nTitle: Untangling waves and mean flows via PDE-based Lagrangian filtering \nAbstract: Oceanic flows are typically composed of wave and mean motions with a wide range of overlapping temporal scales\, making separation between the two types of motion in wave resolving numerical simulations challenging. Lagrangian filtering – whereby a temporal filter is appliedin the frame of the flow – is an effective way to overcome this challenge\, allowing clean separation of waves from mean flow based on frequency separation in a Lagrangian frame. In this talk\, I will present an efficient method for finding the Lagrangian mean and associated wave component using online or offline low-pass filtering without particle tracking. This method is model-agnostic\, but I’ll introduce a new package in Oceananigans (Julia software for fast\, friendly\, flexible\, ocean-flavored fluid dynamics on CPUs and GPUs) that allows model output to be easily and efficiently processed to determine the wave and mean components. Finally\, I’ll show some applications of this method.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/semester-1-week-9-dr-lois-baker-university-of-edinburgh/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20251107T140500
DTEND;TZID=Europe/London:20251107T145500
DTSTAMP:20260412T204135
CREATED:20250710T152626Z
LAST-MODIFIED:20260119T125631Z
UID:437-1762524300-1762527300@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 1\, Week 8: Prof James McLaughlin\, Northumbria University
DESCRIPTION:Academic webpage \nTitle: Oscillatory Reconnection \nAbstract: Magnetic reconnection is a fundamental plasma process at the heart of many dynamic events such as solar flares. These are clearly time-dependent events\, and so we require time-dependent reconnection models to capture this dynamic behaviour. In this talk\, I will describe ongoing investigations into “Oscillatory Reconnection”: a type of time-dependent\, wave-generating reconnection. This will include 2D and 3D nonlinear magnetohydrodynamic (MHD) numerical models that involve reconnection\, MHD waves and shock behaviour. At its heart\, Oscillatory Reconnection is a dynamic energy release process and so the results could be of interest to several communities\, including solar physics\, astrophysical\, fusion\, laboratory-based plasma\, computational MHD and space weather communities. \n 
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/semester-1-week-8-prof-james-mclaughlin-northumbria-university/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20251031T140500
DTEND;TZID=Europe/London:20251031T145500
DTSTAMP:20260412T204135
CREATED:20250710T150652Z
LAST-MODIFIED:20260119T125500Z
UID:423-1761919500-1761922500@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 1\, Week 7: Prof Valery Nakariakov\, University of Warwick
DESCRIPTION:Academic webpage \nTitle: Decayless kink oscillations of solar coronal loops as a self-oscillatory process \nAbstract: \nKink oscillations of the decayless class are detected as small amplitude (< 1 Mm) persistent transverse repetitive displacements of solar coronal plasma loops\, occurring without any association with solar flares\, eruptions\, or other impulsive energy releases. The linear correlation of the oscillation periods with the lengths of the oscillating loops demonstrates that the oscillations are natural modes of the loops. The statistical distribution of oscillation amplitudes with the periods shows no pronounced peaks\, suggesting the lack of a periodic driver. Together with the lack of an impulsive excitation\, it suggests that the energy losses are compensated by the interaction of the loop with either quasi-steady or random external plasma flows. In this study\, the decayless regime is associated with the energy supply from coronal plasma flows via the negative friction\, i.e.\, self-oscillations\, and/or random movements of footpoints of the oscillating loop.\n\nThe kink oscillation period is found to be practically independent of noise\, which justifies seismological estimations of the coronal magnetic field. The transition from the large-amplitude rapidly-decaying regime to the low-amplitude decayless oscillations demonstrates that the decay pattern differs from the usually assumed exponential decay.\n\nImplications of this finding for magnetohydrodynamic seismology of the solar corona\, based on the effect of resonant absorption are discussed.\n 
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/prof-valery-nakriakov/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20251024T140500
DTEND;TZID=Europe/London:20251024T145500
DTSTAMP:20260412T204135
CREATED:20250710T150922Z
LAST-MODIFIED:20250710T155344Z
UID:428-1761314700-1761317700@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 1\, Week 6: Independent Learning Week\, No Seminar
DESCRIPTION:
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/week-6-independent-learning-week-no-seminar/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20251017T140500
DTEND;TZID=Europe/London:20251017T145500
DTSTAMP:20260412T204135
CREATED:20250710T145945Z
LAST-MODIFIED:20260119T125410Z
UID:413-1760709900-1760712900@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 1\, Week 5: Dr Omar Lakkis\, University of Sussex
DESCRIPTION:Academic webpage \nTitle: Adaptive methods and explicit time-stepping \nAbstract: \nAposteriori error analysis for Galerkin finite element methods have proven very successful tool in developing mathematically rigorous adaptive mesh refinement algorithms for implicit/space-time evolution equations.  In this work we extend rigorous adaptivity principles to explicit time-stepping for the wave equation. \nI will review in the first part of the talk the state of the art for the wave equation. In the second part\, I will present recent work in connection to fully practical explicit schemes such as the Leapfrog method and local time step variants thereof. \n\nThis talk is mostly based on joint work with M Grote\, C Santos.\nLocation: TBD
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/dr-omar-lakkis-university-of-sussex/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20251010T140500
DTEND;TZID=Europe/London:20251010T145500
DTSTAMP:20260412T204135
CREATED:20250710T150248Z
LAST-MODIFIED:20260119T125036Z
UID:417-1760105100-1760108100@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 1\, Week 4: Prof Fabian Spill\, University of Birmingham
DESCRIPTION:Academic webpage \nTitle: The Role of Geometry\, Topology and Mechanics in Physiology and Disease \nAbstract: \nMolecular networks underpin all cellular functions\, including metabolism\, division\, and migration. These networks are frequently altered in disease and are common targets for therapeutic intervention. Many key molecular components are associated with the plasma membrane or are localized within organelles such as mitochondria and the endoplasmic reticulum (ER). Notably\, the spatial\, geometrical\, and topological organization of cells and organelles is highly dynamic and varies with cell type\, physiological state\, and environmental context. For instance\, mitochondria can exist as discrete\, spherical structures or as extensive\, fused networks\, while the ER can adopt sheet-like or tubular morphologies. \n\nA major open question is how the organization of cellular and subcellular structures contributes to physiological regulation and how disruptions in this organization influence disease progression and therapeutic response. \n\nIn this talk\, I will present recent and ongoing work demonstrating that spatial organization is a key determinant of cellular function. First\, I will discuss how mitochondrial architecture influences metabolic pathway activity in the context of diabetes. Next\, I will explore how metabolic interactions between cancer cells and stromal cells drive tumour progression. Finally\, I will show how the structural organization of the ER into sheets and tubules regulates collective cell migration during wound healing\, in a manner that is dependent on cell morphology.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/dr-fabian-spill-university-of-birmingham/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20251003T140500
DTEND;TZID=Europe/London:20251003T145500
DTSTAMP:20260412T204135
CREATED:20250710T150416Z
LAST-MODIFIED:20250710T151247Z
UID:420-1759500300-1759503300@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Semester 1\, Week 3: Unassigned
DESCRIPTION:Academic webpage \nTitle: TBA \nAbstract: TBA \nLocation: TBD
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/unassigned/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20250530T140000
DTEND;TZID=Europe/London:20250530T150000
DTSTAMP:20260412T204135
CREATED:20250204T093033Z
LAST-MODIFIED:20250204T100636Z
UID:376-1748613600-1748617200@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Prof. Denise Kirschner\, University of Michigan
DESCRIPTION:Academic webpage \nTitle: TBA \nAbstract: TBA \nLocation: TBD
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/prof-denise-kirschner-university-of-michigan/
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20250502T140000
DTEND;TZID=Europe/London:20250502T150000
DTSTAMP:20260412T204135
CREATED:20250115T162858Z
LAST-MODIFIED:20250422T144625Z
UID:356-1746194400-1746198000@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Dr Eric William Hester\, University of Bath
DESCRIPTION:Academic webpage \nTitle: Modelling multiphase matter: from microparticles to mega-icebergs \nAbstract: The world is multiphase. Water and ice\, rock and lava\, nucleus and cytoplasm. How can we model these systems\, and simulate them efficiently? I’ll start with three examples from my research\, boat drag in dead water\, melting icebergs in salty oceans\, and phase-separating polymers in microparticle experiments. The same patterns recur. A seemingly simple partition into PDEs and boundary conditions belies the murky interface between them. This diffuse interface in turn motivates a host of numerical schemes and mathematical questions. The bulk of my talk will discuss the mathematical tools we need to understand these methods. Signed-distance coordinates give a straightforward vector calculus around arbitrary submanifolds\, and matched asymptotics describes the resulting solutions to arbitrary order. I’ll show how we can use this knowledge to design more accurate and efficient numerical schemes\, and thereby achieve a better understanding of our motivating problems\, before concluding with some bigger questions for multiphase methods.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/dr-eric-william-hester-university-of-bath/
LOCATION:MAT Theatre D
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20250425T140000
DTEND;TZID=Europe/London:20250425T150000
DTSTAMP:20260412T204135
CREATED:20250115T163039Z
LAST-MODIFIED:20250415T133323Z
UID:359-1745589600-1745593200@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Prof. Peter Davidson\, University of Cambridge
DESCRIPTION:Academic Webpage \nTitle: Reversals of the Geodynamo \nAbstract: Somewhat surprisingly\, there is still no convincing model\, or even cartoon\, for reversals of the earth’s magnetic field. This is because the underlying mechanisms are still not understood. While numerical simulations of the geodynamo are\, perhaps\, finally beginning to approach a dynamically relevant regime\, they still cannot reproduce realistic reversals of the terrestrial field. In this talk a new model of reversals is presented\, a model whose predictions are reasonably earth like.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/prof-peter-davidson-university-of-cambridge/
LOCATION:MAT Theatre D
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20250328T140000
DTEND;TZID=Europe/London:20250328T150000
DTSTAMP:20260412T204135
CREATED:20241010T151358Z
LAST-MODIFIED:20250324T112834Z
UID:334-1743170400-1743174000@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Prof. Patrick Farrell\, University of Oxford
DESCRIPTION:Academic webpage: https://www.maths.ox.ac.uk/people/patrick.farrell \nTitle: Designing conservative and accurately dissipative numerical integrators in time \nAbstract: Numerical methods for the simulation of transient systems with structure-preserving properties are known to exhibit greater accuracy and physical reliability\, in particular over long durations. These schemes are often built on powerful geometric ideas for broad classes of problems\, such as Hamiltonian or reversible systems. However\, there remain difficulties in devising higher-order-in-time structure-preserving discretizations for nonlinear problems\, and in conserving non-polynomial invariants. \nIn this work we propose a new\, general framework for the construction of structure-preserving timesteppers via finite elements in time and the systematic introduction of auxiliary variables. The framework reduces to Gauss methods where those are structure-preserving\, but extends to generate arbitrary-order structure-preserving schemes for nonlinear problems\, and allows for the construction of schemes that conserve multiple higher-order invariants. We demonstrate the ideas by devising novel schemes that exactly conserve all known invariants of the Kepler and Kovalevskaya problems\, arbitrary-order schemes for the compressible Navier-Stokes equations that conserve mass\, momentum\, and energy\, and provably dissipate entropy\, and helicity-conservative/energy-dissipative schemes for the Parker problem of magnetohydrodynamics.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/prof-patrick-farrell-university-of-oxford/
LOCATION:MAT Theatre D
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20250314T140500
DTEND;TZID=Europe/London:20250314T150000
DTSTAMP:20260412T204135
CREATED:20241006T212318Z
LAST-MODIFIED:20250310T110052Z
UID:285-1741961100-1741964400@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Dr Christopher Prior\, Durham University
DESCRIPTION:Academic webpage: https://www.durham.ac.uk/staff/christopher-prior/ \nTitle: Predicting protein dynamics using writhe \nAbstract: The advent of AlphaFold has steered the fundamental questions on protein structure towards understanding their dynamics in their native state\, rather than the static crystal states routinely predicted. One critical tool in our arsenal is small angle x-ray scattering (SAXS) which allows\, with significant modelling\, for the imaging of protein dynamics in solution. However\, modelling proteins by standard force field methods is inhibitively computationally expensive\, so alternative methods are required for effective and routine interpretation of SAXS data. I will present a method and code for SAXS interpretation (Carbonara)\, which used constraints on the geometry and topology of proteins which we have derived from structural data. Hopefully it will be of interest for the potential audience at St Andrews that the fundamental underlying quantity in this method is the writhe\, a quantity routinely used in solar and astrophysical modelling to quantify and constrain the topology of magnetic flux ropes. In doing so I will briefly highlight the interesting history of how the fields of long chain biology and solar magnetic fields have both provided insight to each other.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/dr-christopher-prior-durham-university/
LOCATION:MAT Theatre D
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20250228T140500
DTEND;TZID=Europe/London:20250228T150000
DTSTAMP:20260412T204135
CREATED:20241008T090634Z
LAST-MODIFIED:20250224T125009Z
UID:332-1740751500-1740754800@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Dr Robert Teed\, University of Glasgow
DESCRIPTION:Academic webpage: https://www.gla.ac.uk/schools/mathematicsstatistics/staff/robertteed/ \nTitle: Numerically modelling the magnetic field generation of Earth’s core \nAbstract: \nPlanetary magnetic fields are produced by dynamo action through turbulent motions of an electrically conducting fluid within the interior of the planet. Numerical experiments of dynamo action relevant to Earth’s magnetic field have produced different regime branches identified within bifurcation diagrams [1].\n\nNotable are distinct branches in which the resultant magnetic field is either weak or strong (when compared with the fluid flow). Such branches can be found within a small window of parameter space\, as long predicted [2]. Weak field solutions can be identified by the prominent role of viscosity on the motion whereas the magnetic field has a leading order effect on the flow in strong field solutions. One measure of the success of numerical models of the geodynamo is the ability to replicate the expected balance between forces operating within Earth’s core; Coriolis (rotational) and Lorentz (magnetic) forces are predicted to be most important. The value of considering lengthscale dependent force balances [3] and ‘gradient-free’ solenoidal forces has been highlighted recently [4].\n\nI will review the approach in numerically modelling the geodynamo and the challenges in doing so. I will discuss the branches/bifurcations of dynamo action previously explored in numerical simulations. Furthermore\, in new results\, I shall highlight that the expected force balance of Earth’s core can be preserved as input parameters of numerical simulations are moved towards more realistic values.\n\n[1] E. Dormy et al\, Fluid Dynamics Res. 50\, 011415 (2018)\n[2] P. Roberts\, In: Cupal\, I. (ed.)\, Proc. First Int. Workshop on Dynamo Theory and the Generation of the Earth’s Magnetic Field pp. 7–12. Czech. Geophys. Inst. Rep (1979)\n[3] T. Schwaiger et al\, Geophys. J. Inter. 219\, S101–S114 (2019)\n[4] R. J. Teed & E. Dormy\, J. Fluid Mech. 964\, A26 (2023)
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/dr-robert-teed-university-of-glasgow/
LOCATION:MAT Theatre D
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20250221T140500
DTEND;TZID=Europe/London:20250221T150000
DTSTAMP:20260412T204135
CREATED:20241006T212011Z
LAST-MODIFIED:20250217T133215Z
UID:283-1740146700-1740150000@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Prof Pavel S. Berloff\, Imperial College London
DESCRIPTION:Academic webpage: https://www.ma.imperial.ac.uk/~pberloff/ \nTitle: Oceanic Vortex Pulsars\n\n\nAbstract: Theoretical studies of coherent vortices have a half-century history and in many ways have become classics of geophysical fluid dynamics. Some recent results will be presented on a new class of stable and ever-living coherent vortices on stratified background shears. These features\, referred to as “vortex pulsars”\, are fundamentally non-isolated\, and also asymmetric and nonstationary. Two distinctly different families of solutions — “strong” and “weak” — will be discussed.\n 
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/prof-pavel-s-berloff-imperial-college-london/
LOCATION:MAT Theatre D
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20250214T140500
DTEND;TZID=Europe/London:20250214T150000
DTSTAMP:20260412T204135
CREATED:20241024T152219Z
LAST-MODIFIED:20250123T125349Z
UID:338-1739541900-1739545200@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Dr Gabriel Barrenechea\, University of Strathclyde
DESCRIPTION:Affiliation: University of Strathclyde\, UK \nAcademic Webpage \nTitle: A reduced model for a problem in non-Newtonian fluid mechanics \nAbstract: We propose a finite element discretisation of a three-dimensional non-Newtonian flow whose dynamics are described by an Upper Convected Maxwell model.\nFirst\, a one-directional simplification of the UCM problem is made\, so the main\nvariables are velocity\, pressure\, and one vector which acts as the “square root”\nof the stress tensor. For this model a finite element method is proposed and analysed.\nThe scheme preserves structure in the sense that the velocity is divergence-free and the overall discretisation is energy consistent with the underlying\nproblem. We investigate the problem’s complexity and devise relevant timestepping strategies for effcient solution realisation. We showcase the method with several numerical experiments\, confirm the theory and demonstrate the efficiency of the scheme.\n 
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/338/
LOCATION:MAT Theatre D
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20241129T140500
DTEND;TZID=Europe/London:20241129T150000
DTSTAMP:20260412T204135
CREATED:20240405T075119Z
LAST-MODIFIED:20241125T003156Z
UID:232-1732889100-1732892400@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Prof.  José A. Carrillo\, University of Oxford
DESCRIPTION:Affiliation: University of Oxford\,  UK \nAcademic webpage \nTitle: Aggregation-Diffusion Equations for Collective Behaviour in the Sciences\n\nAbstract:\nMany phenomena in the life sciences\, ranging from the microscopic to macroscopic level\, exhibit surprisingly similar structures. Behaviour at the microscopic level\, including ion channel transport\, chemotaxis\, and angiogenesis\, and behaviour at the macroscopic level\, including herding of animal populations\, motion of human crowds\, and bacteria orientation\, are both largely driven by long-range attractive forces\, due to electrical\, chemical or social interactions\, and short-range repulsion\, due to dissipation or finite size effects. Various modelling approaches at the agent-based level\, from cellular automata to Brownian particles\, have been used to describe these phenomena. An alternative way to pass from microscopic models to continuum descriptions requires the analysis of the mean-field limit\, as the number of agents becomes large. All these approaches lead to a continuum kinematic equation for the evolution of the density of individuals known as the aggregation-diffusion equation. This equation models the evolution of the density of individuals of a population\, that move driven by the balances of forces: on one hand\, the diffusive term models diffusion of the population\, where individuals escape high concentration of individuals\, and on the other hand\, the aggregation forces due to the drifts modelling attraction/repulsion at a distance. The aggregation-diffusion equation can also be understood as the steepest-descent curve (gradient flow) of free energies coming from statistical physics. Significant effort has been devoted to the subtle mechanism of balance between aggregation and diffusion. In some extreme cases\, the minimisation of the free energy leads to partial concentration of the mass. Aggregation-diffusion equations are present in a wealth of applications across science and engineering. Of particular relevance is mathematical biology\, with an emphasis on cell population models. The aggregation terms\, either in scalar or in system form\, is often used to model the motion of cells as they concentrate or separate from a target or interact through chemical cues. The diffusion effects described above are consistent with population pressure effects\, whereby groups of cells naturally spread away from areas of high concentration. This talk will give an overview of the state of the art in the understanding of aggregation-diffusion equations\, and their applications in mathematical biology.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/prof-jose-antonio-carrillo-oxford/
LOCATION:Physics Theatre C
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20241122T140500
DTEND;TZID=Europe/London:20241122T150000
DTSTAMP:20260412T204135
CREATED:20240416T085115Z
LAST-MODIFIED:20241117T225535Z
UID:237-1732284300-1732287600@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Dr. Niklas Kolbe\, RWTH Aachen
DESCRIPTION:Affiliation: RWTH Aachen \nAcademic Webpage \nTitle: Central finite volume schemes for coupled hyperbolic models \nAbstract: Various real-world problems in two-phase dynamics\, multi-scale processes and networks can be addressed by coupling hyperbolic models at a static interface. We propose a new relaxation based approach for the coupling of general hyperbolic systems\, in which the Lax curves of the coupled systems are not required. The approach is based on a relaxation limit taken at the coupling interface and embedded in an asymptotic preserving finite volume method. The role of the modified coupling condition is discussed and applications in traffic flow and vascular networks are presented.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/dr-niklas-kolbe-rwth-aachen/
LOCATION:Physics Theatre C
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20241115T140500
DTEND;TZID=Europe/London:20241115T150000
DTSTAMP:20260412T204135
CREATED:20240529T081934Z
LAST-MODIFIED:20241107T212044Z
UID:249-1731679500-1731682800@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Dr. Cathal Cummins\, Heriot-Watt University
DESCRIPTION:Affiliation: Heriot Watt University \nAcademic webpage \nTitle: Resonance and viscous losses in wave energy systems \nAbstract:\nWave Energy Converters (WECs) harness the motion of ocean waves to generate renewable energy\, with sometimes complex dynamics underlying their performance. This talk explores the mathematical modelling of two leading types of WECs\, built here in Scotland. Each has distinct characteristics\, and each exhibits resonance. While resonance is beneficial for one of the WECs\, it is something to be avoided in the other. We will examine the underlying principles of these resonances and reveal how the standard mathematical framework (inviscid potential flow) breaks down under conditions of resonance\, partly due to viscous dissipation. A method will be introduced to account for viscous damping within a potential flow framework\, known as viscous potential flow.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/dr-cathal-cummins-heriot-watt-university/
LOCATION:Phys Theatre A
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20241011T140000
DTEND;TZID=Europe/London:20241011T150000
DTSTAMP:20260412T204135
CREATED:20240429T105425Z
LAST-MODIFIED:20241006T210101Z
UID:246-1728655200-1728658800@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Prof. Jacek Banasiak\, University of Pretoria
DESCRIPTION:Academic Webpage \nTitle: Life cycle of mosquitoes and malaria – a journey through asymptotic analysis and monotone systems\nAuthors: J. Banasiak\, S. Y. Tchoumi and M. Bime Ghakanyuy\, University of Pretoria \nAbstract:  \nDue to the presence of populations with widely different vital rates\, such as mosquitoes and humans\, malaria dynamics offers rewarding examples of multiscale models represented by regularly and singularly perturbed systems of differential equations [3\,5\,6]. Recent improvements in their analysis [1\,2] allow for significantly simplifying such models without losing salient features and their original long-term dynamics. Moreover\, in many cases\, the application of the singular perturbation theory leads to simplified models that are monotone and thus allow for an even more comprehensive analysis. We illustrate the theoretical results with concrete models describing the spreading of malaria [3] and the gonotrophic cycle of mosquitoes [4\,7]. \nLiterature\n[1] F.C. Hoppensteadt\, Singular perturbations on the infinite interval\, Trans. Amer. Math. Soc. 123 (1966) 521–535.\n[2] J. Banasiak\, A note on the Tikhonov theorem on an infinite interval\, Vietnam J. Math. 49 (2021)\, no. 1\, 69–86.\n[3] J. Banasiak\, S.Y. Tchoumi\, Multiscale malaria models and their uniform in-time asymptotic analysis\, Mathematics and Computers in Simulation\, 221 (2024)\, 1 – 18.\n[4] G.A. Ngwa\, M.I. Teboh-Ewungkem\, Y. Dumont\, R. Ouifki\, J. Banasiak\, On a three-stage structured model for the dynamics of malaria transmission with human treatment\, adult vector demographics and one aquatic stage\, J. Theoret. Biol. 481 (2019) 202–222.\n[5] P. Rashkov\, B.W. Kooi\, Complexity of host-vector dynamics in a two-strain dengue model\, J. Biol. Dyn. 15 (1) (2021) 35–72.\n[6] P. Rashkov\, E. Venturino\, M. Aguiar\, N. Stollenwerk\, B.W. Kooi\, On the role of vector modeling in a minimalistic epidemic model\, Math. Biosci. Eng. 16 (5) (2019) 4314–4338.\n[7] J. Banasiak\, G. Ngwa\, M. Bime\, The Impact of Mating on Modeling Mosquito Dynamics: A Mathematical Investigation\, in preparation.\n \n 
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/prof-jacek-banasiak-university-of-pretoria/
LOCATION:Phys Theatre A
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20241004T140000
DTEND;TZID=Europe/London:20241004T150000
DTSTAMP:20260412T204135
CREATED:20231206T113853Z
LAST-MODIFIED:20241002T193409Z
UID:188-1728050400-1728054000@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Dr. Karen Meyer\, University of Dundee
DESCRIPTION:Academic webpage \nTitle: Persistence in Solar Physics\n\n\nAbstract: \n\nPersistence\, or long memory\, is of longstanding interest in solar physics\, having first been identified in time series of sunspot numbers in the seminal paper by Mandelbrot and Wallis (1969): “Some long‐run properties of geophysical records”. They used a method called Rescaled Range Analysis (R/S) to determine a Hurst exponent\, H=0.93\, which is indicative of strong persistence. It has since been suggested that for sunspot numbers\, and indeed most times series of solar quantities\, R/S is not an appropriate method for estimating persistence due to the non-stationary nature of the time series. Detrended fluctuation analysis (DFA) has been proposed as a more suitable method for estimating persistence\, and has since been widely used in the analysis of solar and geo-physical time series. However\, DFA is known to introduce uncontrolled bias and is in fact inappropriate for non-stationary processes (Bryce & Sprague\, 2012).\n\nHere\, we assume an alternative class of long-memory models\, more commonly found in statistics and econometrics: fractionally integrated processes. We revisit solar physics time series such as sunspot number and total solar irradiance with more robust estimators\, and identify higher persistence than previous studies\, as well as persistence over timescales significantly shorter than previously identified.\n\nWe also consider persistence in time series of quantities derived from solar physics simulations\, demonstrating that these simulations capture the memory structure that is present in the observational input data. Further\, we provide an algorithm for the quantitative assessment of simulation burn-in: the time after which a quantity has evolved away from its arbitrary initial condition to a physically more realistic state.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/dr-karen-meyer-dundee/
LOCATION:Phys Theatre A
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/London:20240503T110000
DTEND;TZID=Europe/London:20240503T120000
DTSTAMP:20260412T204135
CREATED:20240206T092801Z
LAST-MODIFIED:20240606T145734Z
UID:206-1714734000-1714737600@applied-mathematics.wp.st-andrews.ac.uk
SUMMARY:Dr. Enrico Camporeale\, Queen Mary
DESCRIPTION:Affiliation: Queen Mary University \nAcademic Webpage \n  \nTitle: Data-Driven Discovery of Fokker-Planck Equation for the Earth’s Radiation Belts Electrons Using Physics-Informed Neural Networks \nAbstract: We use the framework of Physics-Informed Neural Network (PINN) to solve the inverse problem associated with the Fokker-Planck equation for radiation belts’ electron transport\, using 4 years of Van Allen Probes data. Traditionally\, reduced models have employed a diffusion equation based on the quasilinear approximation. We show that the dynamics of “killer electrons” is described more accurately by a drift-diffusion equation\, and that drift is as important as diffusion for nearly-equatorially trapped ∼1 MeV electrons in the inner part of the belt. Moreover\, we present a recipe for gleaning physical insight from solving the ill-posed inverse problem of inferring model coefficients from data using PINNs. Furthermore\, we derive a parameterization for the diffusion and drift coefficients as a function of L only\, which is both simpler and more accurate than earlier models. Finally\, we use the PINN technique to develop an automatic event identification method that allows identifying times at which the radial transport assumption is inadequate to describe all the physics of interest.
URL:https://applied-mathematics.wp.st-andrews.ac.uk/event/dr-enrico-camporeale-queen-mary/
LOCATION:MAT Theatre B
END:VEVENT
END:VCALENDAR